JP2000046105A - Base isolation bed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation bed capable of surely performing base isolation from a shake in an omni-direction of 360 deg. horizontal direction, and capable of providing miniaturization with a wide range of application, and further with a cost reduced to be excellent in handling. SOLUTION: A bed plate 2 mounting a protection article, base plate 1, and an intermediate plate 3 are provided, three or more spherical concave surfaces 4 are respectively formed in upper/lower both surfaces of the intermediate plate 3, and a free bearing 5 having a spherical rotary body 5a in a tip end, opposed to each spherical concave surface 4 formed in the upper/lower both surfaces of the intermediate plate 3, is fixedly provided in an upper surface of the base plate 1 and a lower surface of the bed plate 2 so as to abut to a center position of the opposed spherical concave surface 4, and the bed plate 2 and the intermediate plate 3 are mounted swivelably in an omni-direction of 360 deg. horizontal direction with the plates left as holding a horizontal condition, by rolling action of each spherical concave surface 4 and spherical rotary body 5a. Even when the base plate 1 is shaken by an earthquake or the like, since this shaking is damped by a shake absorbing mechanism of upper/lower two-step constitution, a protection article mounted on the bed plate 2 is prevented from dropping by a tumble.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation table for absorbing shaking caused by an earthquake or the like, and more particularly to a seismic isolation suitable for protecting relatively small articles such as arts and crafts and antiques. About the stand.

[0002]

2. Description of the Related Art Conventionally, various seismic isolation devices have been developed and provided in order to absorb a shaking caused by an earthquake or the like to prevent a fall or a fall. For example, as a seismic isolation device for a large building such as a building, a vibration is caused by interposing a damper in which a polymer material having elasticity and a metal plate are alternately stacked between a foundation portion of the building and an upper structure. And the like are known.

On the other hand, seismic isolation tables for protecting relatively small articles such as arts and crafts and antiques are shown in FIG.
The following are known. The seismic isolation table of FIG. 13 has two arc-shaped rails 82, 82 on the upper surface of a lower plate 81.
And two wheels 84, 84 having rolling rollers 83, 83 connected to both ends thereof are laid over the two rails 82, 82, and an intermediate plate 85 is mounted on the two wheels 84, 84. Is fixed.

On the upper surface of the middle plate 85, two arc-shaped rails 86, 86 are attached to the rails 82, 86 of the lower plate 81.
82, the two rails 86, 8
6, two wheels 88, 88 having rolling rollers 87, 87 connected to both ends thereof are laid over the wheel 6, and a base plate 89 for mounting a protective article on the two wheels 88, 88 is fixed. When the building shakes due to an earthquake or the like, the shaking is absorbed by the rolling action of the two sets of rails and wheels arranged orthogonally, and the shaking of the earthquake or the like is attenuated and transmitted to the base plate 89 on which the protective article is placed. .

[0005]

However, in the above-mentioned conventional seismic isolation table, rails and wheels must be provided in two stages in the X-axis direction and the Y-axis direction. However, there is a problem that the structure is complicated and bulky because it is necessary to combine auxiliary vibration absorbing mechanisms such as the above. In addition, because of the complicated structure, it is difficult to make the seismic isolation table smaller than a certain size, and if it is used for relatively small protective articles such as arts and crafts and antiques, it will be necessary to fit individual protective articles. There was a problem that it had to be made by special order and it became expensive.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and it is possible to surely isolate the shaking in all directions of 360 ° in the horizontal direction, and at the same time, it is possible to reduce the size and apply the present invention. The purpose is to provide a seismic isolation table that is wide, inexpensive, and excellent in handling.

[0007]

In order to achieve the above object, a seismic isolation table according to claim 1 includes a base plate on which a protective article is mounted, a substrate mounted on an installation surface such as a floor, and the base plate. And a middle plate interposed between the base plate and the upper and lower surfaces of the middle plate, on each of which three or more spherical concave surfaces are formed, and on the upper surface of the substrate and the lower surface of the base plate. The free bearing provided with a rotatable spherical rotating body at the tip is opposed to each spherical concave curved surface formed on the upper and lower surfaces of the middle plate so that the free bearing abuts the center position of the opposed spherical concave curved surface. The rolling action between the spherical concave curved surface and the spherical rotating body that are in contact with each other makes the base plate and the intermediate plate swingable in all directions of 360 ° in the horizontal direction while maintaining the horizontal state. It is characterized by the following.

According to a second aspect of the present invention, there is provided a base isolation plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and a middle plate interposed between the base plate and the substrate. And three or more spherical concave curved surfaces are formed on the upper surface of the substrate and the lower surface of the base plate, respectively, and the upper and lower surfaces of the middle plate are formed on the upper surface of the substrate and the lower surface of the base plate, respectively. A free bearing having a rotatable spherical rotator at its tip is fixedly provided so as to abut the center position of the opposed spherical concave curved surface so as to face each of the spherical concave curved surfaces. By the rolling action of the spherical concave curved surface and the spherical rotating body, the base plate and the intermediate plate are kept in the horizontal direction 3 while maintaining the horizontal state.
It is characterized by being swingable in all directions of 60 °.

[0009] A seismic isolation table according to a third aspect of the present invention is a base plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and an intermediate plate interposed between the base plate and the substrate. On the upper and lower surfaces of the middle plate, three or more spherical concave curved surfaces are respectively formed, and on the upper surface of the substrate and the lower surface of the base plate, each formed on the upper and lower surfaces of the middle plate. Spherical concave curved surfaces are respectively formed so as to face the spherical concave curved surfaces, and a rotatable spherical rotating body is sandwiched between the spherical concave curved surfaces opposed to each other vertically, and the spherical concave curved surfaces that come into contact with these spherical concave curved surfaces and the spherical rotation By the rolling action with the body, the base plate and the intermediate plate can be swung in all directions of 360 ° in the horizontal direction while maintaining the horizontal state.

According to a fourth aspect of the present invention, there is provided a seismic isolation table including a base plate on which a protective article is mounted, a substrate mounted on an installation surface such as a floor, and a middle plate interposed between the base plate and the substrate. And three or more spherical concave curved surfaces are formed on both upper and lower surfaces of the middle plate, respectively.
A spherical concave surface is formed on the upper surface of the substrate so as to face each spherical concave surface formed on the lower surface of the middle plate, and a spherical rotating body rotatable between the opposed spherical concave surfaces. And a free bearing having a rotatable spherical rotating body at the tip thereof is provided on the lower surface of the base plate so as to face each spherical concave curved surface formed on the upper surface of the middle plate. It is fixed so as to abut on the center position of the concave curved surface, and the rolling action of each of the spherical concave curved surfaces and the spherical rotator abuts on the base plate and the intermediate plate while keeping the horizontal state in the horizontal direction. It is characterized in that it can swing in all directions of 360 °.

According to a fifth aspect of the present invention, in the seismic isolation table of the first to fourth aspects, a brake mechanism for damping horizontal swing is provided between the substrate and the middle plate and between the middle plate and the base plate. It is characterized by the following.

According to a sixth aspect of the present invention, in the seismic isolation table of the fifth aspect, the brake mechanism is a contact friction type brake mechanism utilizing frictional resistance.

According to a seventh aspect of the present invention, in the seismic isolation table of the fifth aspect, the brake mechanism is a magnetic repulsion type brake mechanism utilizing magnetic repulsion between permanent magnets having the same polarity. It is assumed that.

According to an eighth aspect of the present invention, there is provided the seismic isolation table according to the fifth aspect, wherein the brake mechanism comprises a curved surface in which the peripheral portion of the spherical concave curved surface rises more steeply than the center portion. It is a mechanism.

A quake isolator according to a ninth aspect of the present invention is the quake isolator according to any one of the first to eighth aspects, wherein a spherical concave surface located above the middle plate with the middle plate as a boundary, and a lower surface below the middle plate. Is characterized by having different radii of curvature of the spherical concave curved surface located at the position.

[0016]

The object to be protected from earthquakes, for example, arts and crafts and antiques, is placed on the base plate of the seismic isolation table of the present invention. When the building shakes due to an earthquake or the like, the board in contact with the floor surface of the building also shakes, but the base plate tends to stop at that position due to inertia. For this reason, the vibration absorption mechanism composed of a spherical concave surface and a free bearing formed between the substrate and the intermediate plate, the intermediate plate and the base plate, respectively, or the vibration absorption mechanism composed of the spherical concave surface and the spherical rotator causes a rolling action due to an earthquake or the like. The shaking is attenuated and hardly reaches the base plate.

Further, the swing absorbing mechanism composed of the spherical concave curved surface and the free bearing or the spherical rotating body can swing freely in all directions of 360 ° in the horizontal direction while maintaining the horizontal state. It can be attenuated effectively.

When a brake mechanism such as a contact friction type, a magnetic repulsion type, or a gravity pull back type is provided,
Appropriate braking is applied to the moderate sway of the middle plate and the base plate in the horizontal direction, so that the sway of the middle plate and the base plate, which tends to continue to shake even after the earthquake, can be quickly attenuated. Further, it is possible to prevent the middle plate and the base plate from shaking greatly and falling off from the substrate during an earthquake.

Further, with the middle plate as a boundary, for example, the radius of curvature of the spherical concave surface located below the middle plate is reduced (that is, the depth of the spherical concave surface is increased), and the radius of curvature is increased above the middle plate. If the radius of curvature of the located spherical concave surface is made large (that is, the depth of the spherical concave surface is made shallow), violent shaking with a short period is efficiently attenuated by the lower spherical concave surface portion having a small radius of curvature, and Small fluctuations having a long period can be efficiently attenuated by the upper spherical concave curved portion having a large radius of curvature. For this reason, it is possible to extremely effectively attenuate vibrations of various periods and intensities.

Further, since the middle plate and the base plate swing while moving in parallel in all directions of 360 ° in a horizontal direction while keeping the horizontal position, the base plate is tilted and the protective article slips or falls down during an earthquake. There is no such thing.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show a first embodiment of a seismic isolation table according to the present invention. In the figure, reference numeral 1 denotes a substrate placed directly on a floor or a mounting surface such as a display stand or via a seismic isolation table mounting bracket 7, and 2 denotes a protective article such as arts and crafts or antiques on its upper surface. A middle plate 3 is interposed between the base plate 1 and the base plate 2. A spherical concave curved surface 4 having a predetermined radius of curvature R is provided on both upper and lower surfaces of the middle plate 3. Each is formed at the vertex position of a triangle.

The upper surface of the substrate 1 is provided with a rotatable spherical rotator 5a at the tip thereof so as to face each of the three spherical concave curved surfaces 4 formed on the lower surface of the intermediate plate 3. Three free bearings 5 are fixedly provided respectively in alignment with the center position of the spherical concave curved surface 4, and the three spherical concave curved surfaces formed on the upper surface of the middle plate 3 are provided on the lower surface of the base plate 2. The three free bearings 5 each having a rotatable spherical rotating body 5 a at the end thereof are fixedly opposed to each of the spherical surfaces 4 so as to coincide with the center of the spherical concave curved surface 4.

As described above, each of the three spherical concave curved surfaces 4 formed on the upper and lower surfaces of the middle plate 3 is connected to the spherical surface of each free bearing 5 fixed on the upper surface of the substrate 1 and the lower surface of the base plate 2. The base plate 2 and the intermediate plate 3 are configured to be freely swingable in all directions of 360 ° in the horizontal direction while being kept horizontally on the substrate 1 by being brought into contact with the rotating body 5a.

The radius of curvature R and the radius L of the curved surface of the spherical concave curved surface 4 vary depending on the size and weight of the protective article placed on the base plate 2, the maximum vibration and period of the vibration to be absorbed, and the like. The optimum curvature radius R and the curved surface passing diameter L are selected.

If the radius of curvature R is changed between the spherical concave curved surface on the upper surface side and the spherical concave curved surface on the lower surface side of the middle plate 4, the vibrating vibration having a short cycle can be efficiently performed on the spherical concave curved surface having a small radius of curvature. It can attenuate well and efficiently attenuate small long-period shaking on the spherical concave surface with a large radius of curvature, and it is more effective against various vibrations from initial tremor to main shock and aftershock during an earthquake. Can be dealt with effectively.

As the intermediate plate 3 forming the spherical concave curved surface 4, a hard material which is hard to change over time, such as a metal (iron, brass, stainless steel, aluminum, etc.) or a hard synthetic resin, is mainly used. However, the present invention is not limited to these. For example, the surface of the spherical concave curved surface 4 made of wood or the like may be lined with metal or hard synthetic resin, or as described later (FIG. 12). 4 may be manufactured separately, and the spherical concave curved surface 4 may be bonded to both surfaces of the core material.

FIGS. 2A and 2B show a specific example of the structure of the free bearing 5. (A) shows an upward free bearing, and (b) shows a downward free bearing. A spherical rotating body 5 made of steel ball or hard resin or the like is shown.
a is located at the tip end surface of the bearing base 5b and is embedded so as to be surrounded by the bearing 5c. The sliding action of the bearing 5c allows the spherical rotating body 5a to freely rotate 360 degrees in any direction. Things.

FIG. 3 shows a specific example of the structure of the seismic isolation table mounting bracket 7. In the illustrated example, the seismic isolation table mounting bracket 7 is
a, a cylindrical damper 7b made of rubber, a coil spring or the like attached to the lower surface of the substrate 1
b, and a slider 7 fixed to the lower end of the threaded shaft 7c
d, lock nuts 7e and 7f for fixing the position, and a ring 7g for preventing the shaft from coming off. The slider 7d is inserted into a pair of left and right slide rails 20, 20 previously laid on an installation surface such as a floor surface or a display stand, and positions the seismic isolation table.

First, the installation of the seismic isolation table having the above structure and the display of the protective articles will be described. In addition, a pair of left and right slide rails 2 for installing the seismic isolation table of the present invention.
It is assumed that 0 and 20 are previously laid at predetermined positions on a display stand or the like as illustrated in FIG.

Now, the seismic isolation table of the present invention is mounted on the slide rail 2.
In order to attach the sliders 7d of the seismic isolation table mounting brackets 7 attached to three lower surfaces of the substrate 1, the sliders 7d are inserted into the pair of left and right slide rails 20, 20, respectively.
The seismic isolation table is moved along the slide rails 20 and 20 to the designated display position. After the seismic isolation table is transported to the designated display position, the lock nuts 7f of the respective seismic isolation table mounting brackets 7 provided on the three lower surfaces of the substrate 1 are rotated and tightened, and the seismic isolation table is fixed at the position.

Next, a level, for example, for leveling the seismic isolation table is placed on the base plate 2 of the seismic isolation table, and while watching this level, the lock nut 7e of each mounting bracket 7 for the seismic isolation table is removed. Turn each and adjust the tilt of the base isolation table to take the level.

After leveling the seismic isolation table in this way,
For example, as shown in FIG. 4, antique articles such as pottery as protective articles are placed on the base plate 2 and covered with a glass case C for display. With the above operations, the installation of the seismic isolation table and the display of the protective articles are completed.

Next, a description will be given of the vibration absorbing operation of the seismic isolation table on which the protective article is placed as described above. When an earthquake or the like occurs and the entire building on which the seismic isolation base is installed shakes, the base plate 1 of the seismic isolation base also shakes together with the building. However,
In the case of the seismic isolation table of the present invention, a first swing absorbing mechanism including three spherical concave curved surfaces 4 and three free bearings 5 is configured between the substrate 1 and the upper middle plate 3. Middle plate 3
And a second swing absorbing mechanism composed of three spherical concave curved surfaces 4 and three free bearings 5 between the upper and lower base plates 2, the two upper and lower two-stage The vibration caused by the earthquake is effectively attenuated by the rolling action of the swing absorbing mechanism and the inertia interaction of the base plate 2 and the protective articles placed thereon due to its own weight. Therefore, it is almost impossible for the protective article placed on the base plate 2 to shake and fall, and it is possible to reliably prevent an accident that the protective article falls down and breaks during an earthquake.

The base plate 2 and the middle plate 3 move in parallel while maintaining the horizontal state by the action of the three spherical concave curved surfaces 4 and the three free bearings 5. , Horizontal 3 without tilting
It can swing freely in all directions of 60 °. For this reason, the same seismic isolation effect can be exerted against shaking in all directions.

Further, since the swing absorbing mechanism composed of the three spherical concave curved surfaces 4 and the three free bearings 5 is formed in two upper and lower stages, the vibration absorbing mechanism of each individual swing absorbing mechanism is compared with the case of the single stage configuration. The swing width can be reduced.
For this reason, the curved surface passing diameter L of the spherical concave curved surface 4 can be reduced, and the seismic isolation table can be made smaller accordingly.

If the radius of curvature of the spherical concave surface 4 located above and below the intermediate plate 3 is changed, the spherical concave surface having a small radius of curvature can be obtained. Effectively attenuates short periods of intense shaking,
Able to efficiently attenuate small long-period fluctuations on the spherical concave surface with a large radius of curvature, and more effectively cope with various vibrations from the initial microshock at the time of the earthquake to the main shock and aftershocks Can be.

Further, since the base plate 2 and the middle plate 3 are supported by the three spherical concave curved surfaces 4 and the three free bearings 5, the base plate 2 and the middle plate 3 swing right and left while always maintaining a horizontal state, and the base plate 2 is moved. There is no such thing that the article placed on it tilts and slides down.

FIG. 5 shows a second embodiment of the seismic isolation table according to the present invention. The second embodiment is different from the first embodiment (FIG. 1) in that a contact friction type brake mechanism for braking the swing of the base plate 2 and the middle plate 3 is provided by each free bearing. It is attached around 5.

That is, a cylindrical brake collar 8 is loosely fitted around each free bearing 5 fixed to the base plate 1 and the base plate 2, and a predetermined surface such as a synthetic resin is The friction member 9 made of a material is fixed. The Breky collar 8 is constantly urged toward the middle plate 3 by a spring 10 which is contracted and arranged around its outer periphery, and the friction member 9 at the tip end surface thereof is pressed against the surface of the spherical concave curved surface 4 by a predetermined pressure. By pressing, a moderate braking force is applied between the base 1 and the middle plate 3 and between the base plate 2 and the middle plate 3 to regulate the amplitude of the sway within a safe range and end the earthquake. Even so, the seismic isolation table is prevented from shaking for a long time.

FIG. 6 shows a third embodiment of the base isolation table according to the present invention. In the third embodiment, a contact friction type brake mechanism is provided at the center of the seismic isolation table, one at a time, in the same configuration as the first embodiment (FIG. 1).

That is, a guide tube 15 is fixedly provided through the upper and lower surfaces at the center position of the middle plate 3, and around the guide tube 15,
A cylindrical brake collar 8 having a friction member 9 fixed to the tip end surface
Is loosely fitted. The Brekey collar 8 is constantly urged toward the middle plate 3 by a spring 10 which is contracted and arranged around the Brekey collar 8, and the friction member 9 on the distal end surface thereof is attached to the base 1.
And the surface of the base plate 2 with a predetermined contact pressure. With the brake mechanism having such a configuration, an appropriate amount of space between the base 1 and the middle plate 3 and between the base plate 2 and the middle plate 3 can be obtained similarly to the above-described second embodiment (FIG. 4). A braking force can be applied.

FIG. 7 shows a fourth embodiment of the seismic isolation table according to the present invention. The fourth embodiment is similar to the first embodiment (FIG. 1) except that a magnetic repulsion type brake mechanism is additionally provided.

That is, a magnetic cylinder 13 made of a permanent magnet such as ferrite is fixedly mounted at the center of the middle plate 3 so as to penetrate through the upper and lower surfaces of the middle plate 3. A magnetic ring 14 made of a permanent magnet such as ferrite having a diameter large enough to be inscribed in the four free bearings 5 is fixed to each of the base plate 1 and the base plate 2.

The magnetic cylinder 13 and the magnetic ring 14 have magnetic poles of the same polarity on their opposing surfaces, for example, as shown in FIG.
The magnetic ring 13 is magnetized so that the inner peripheral surface of the magnetic ring 14 has the N pole when the outer peripheral surface of the magnetic cylinder 13 has the N pole. Therefore, when the base plate 2 and the middle plate 3 deviate from the center position due to shaking or the like, they are pulled back toward the center by the magnetic repulsive force of the magnetic cylinder 13 and the magnetic ring 14, and the base plate 2 and the middle plate 3 are placed on the substrate 1. It is possible to prevent such a situation from being deviated.

When this magnetic repulsion type brake mechanism is employed, the braking force changes smoothly in proportion to the amplitude of the swing, so that an extremely smooth braking can be applied without a sudden braking force being applied. it can.

FIGS. 8A and 8B show a fifth embodiment of the seismic isolation table according to the present invention. In the fifth embodiment,
In the same configuration as the second embodiment (FIG. 5),
In addition to a contact friction type brake mechanism, a gravity pull back type brake mechanism is further added.

That is, the radius of curvature of the peripheral portion of each spherical concave curved surface 4 is reduced to form a curved surface 4a having a large rising slope. As described above, when the peripheral portion of the spherical concave curved surface 4 is a curved surface 4a having a large rising slope, when a large swing reaching the curved surface 4a occurs, the force of pulling back gravity by the steep inclined surface acts as a braking force. So
More reliable and gentle braking can be applied.
For this reason, the base plate 2 and the middle plate 3 move beyond the limit and the substrate 1
It is possible to prevent an unexpected accident such as coming off from above.

FIG. 9 shows a sixth embodiment of the seismic isolation table according to the present invention. The sixth embodiment is similar to the first embodiment described above.
Contrary to the embodiment (FIG. 1), spherical concave curved surfaces 4 and 4 having a predetermined radius of curvature are formed on the base 1 and the base plate 2 respectively, and the free bearing 5 is formed on the middle plate 2 side. Is provided. Thus, even if the spherical concave curved surface 4 and the free bearing 5 are provided in reverse, the same effect can be obtained. In the case of the sixth embodiment,
As the brake mechanism, a contact friction type, a magnetic repulsion type, and a gravity pullback type can be adopted.

FIG. 10 shows a seventh embodiment of the seismic isolation table according to the present invention. In the seventh embodiment, the upper and lower surfaces of the intermediate plate 3, the upper surface of the substrate 1, and the lower surface of the
By forming the spherical concave curved surfaces 4 facing each other and sandwiching the spherical rotating body 16 between the spherical concave curved surfaces 4 facing up and down, the base plate 2 and the intermediate plate 3 can swing on the substrate 1. It is placed. With such a configuration, the structure can be further simplified. In the case of the seventh embodiment, as the brake mechanism, a contact friction type or a gravity retraction type can be adopted.

FIG. 11 shows an eighth embodiment of a base isolation table according to the present invention. In the eighth embodiment, three spherical concave curved surfaces 4 are formed on the upper surface of the substrate 1 and the upper and lower surfaces of the intermediate plate 3, respectively, so that the upper surface of the substrate 1 and the lower surface of the intermediate plate 3 face each other. The spherical rotating body 16 is sandwiched between the spherical concave curved surfaces 4, and the lower end of the base plate 2 is opposed to each of the three spherical concave curved surfaces 4 formed on the upper surface of the middle plate 3, Three free bearings 5 each having a rotatable spherical rotator 5a are fixedly aligned with the center of the spherical concave curved surface 4 respectively. In the case of the eighth embodiment, as the brake mechanism, a contact friction type and a gravity pull-back type are used between the base plate 1 and the middle plate 3, and the brake mechanism is provided between the base plate 2 and the middle plate 3. A contact friction type, a magnetic repulsion type, and a gravity pull-back type can be adopted as the device.

In each of the above embodiments, the case where the spherical concave curved surface 4 is integrally formed on both surfaces of the intermediate plate 3 or the upper surface of the base 1 or the lower surface of the base plate 2 is exemplified. do not have to. For example, taking the case of the middle plate 3 as an example, as shown in FIG. 12A, a plate 18 having a spherical concave curved surface may be bonded to the front and back surfaces of a core plate 17 made of a flat plate. As shown in FIG. 12B, a plate 19 pressed to a spherical concave curved surface may be welded to the front and back surfaces of a core plate 17 made of a flat plate. As the material of the plates 18 and 19, it is desirable to use a hard material that does not easily change over time, such as a metal (iron, brass, stainless steel, aluminum, etc.) or a hard synthetic resin.

Further, in each of the above-described embodiments, a case has been exemplified in which three spherical concave curved surfaces 4 are arranged in three triangles on one plane to constitute a swing absorbing mechanism. However, spherical concave curved surfaces arranged on one plane are provided. The number of 4 is not limited to this number, and may be more. However, considering the actual use condition, it is possible to maintain the horizontal state of the seismic isolation table most stably and reliably.
It is most preferable to use three pieces that can be easily leveled.

Further, in each of the above-described embodiments, the case where the seismic isolation table is installed by using the seismic isolation table mounting bracket 7 and the slide rails 20 and 20 has been exemplified. It is not limited. For example, in places where the slide rails 20 and 20 cannot be laid or in general homes, the seismic isolation table mounting bracket 7 and the slide rails 20 and 2 are used.
Instead of 0, rubber dampers may be laid directly on the four lower corners of the substrate 1 and the height of each rubber damper may be adjusted to level the seismic isolation table. In any case, the base plate 1 of the seismic isolation table must be fixed to a building or a structure that shakes with the earthquake.

Although various embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications and applications can be made in accordance with the gist of the present invention.

[0055]

According to the seismic isolation table of the present invention, the following excellent effects can be exhibited. (1) Employs a vertical two-stage swing absorbing mechanism consisting of a spherical concave curved surface and a free bearing, or a vertical two-stage swing absorbing mechanism consisting of a spherical concave curved surface and a spherical rotating body. Extremely high seismic isolation can be achieved. In addition, since the base plate swings while moving horizontally in all directions of 360 ° while maintaining the horizontal state, the base plate does not tilt, and the protective article placed on the base plate falls or falls down. There is no such thing as.

(2) Since the swing absorption mechanism is constituted by the spherical concave curved surface and the free bearing or the spherical concave curved surface and the spherical rotating body, the conventional seismic isolation system in which the rail and the wheel are combined in the X-axis direction and the Y-axis direction. The structure is simpler than the table,
The seismic isolation table can be downsized.

By changing the radii of curvature of the upper and lower spherical concave surfaces with the middle plate as a boundary, vigorous shaking with a short cycle is efficiently attenuated on the spherical concave surface having a small radius of curvature, and the radius of curvature is further increased. It is possible to efficiently attenuate small shaking with a long period on the concave spherical surface side, and to more effectively cope with various vibrations generated during an earthquake, from initial tremor to main shock and aftershock.

(3) It is possible to flexibly cope with protective articles of various sizes and shapes simply by preparing standardized products of several sizes and shapes. For this reason, it is not necessary to make a seismic isolation table according to each protection article by a special order as in the related art, so that the handling can be simplified and the cost can be significantly reduced.

(4) Since the vibration absorbing mechanism is formed in two stages, the vibration such as an earthquake can be shared and absorbed by the upper and lower two vibration absorbing mechanisms. For this reason, since the horizontal swing width of each swing absorbing mechanism can be reduced, the radius of the curved concave surface for absorbing the swing can be reduced, and the seismic isolation table can be made compact. be able to.

(5) By providing a brake mechanism for damping horizontal vibration between the substrate and the middle plate and between the middle plate and the base plate, the base plate and the middle plate are displaced from the substrate even when a large shake occurs. It can be prevented from coming off and can be used more safely. In particular,
When a magnetic repulsion type brake mechanism is employed, the braking force changes smoothly in proportion to the amplitude of the swing, so that an extremely smooth braking can be applied without applying a sudden braking force.

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment of the present invention, wherein FIG. 1A is a plan view thereof, and FIG. 1B is a sectional view taken along line AA in FIG.

2A is a longitudinal sectional view of an upward free bearing, and FIG. 2B is a longitudinal sectional view of a downward free bearing.

FIG. 3 is an enlarged vertical sectional view showing a specific example of the structure of a seismic isolation table installation bracket.

FIG. 4 is a perspective view showing an example of installation of a seismic isolation table.

FIGS. 5A and 5B show a second embodiment of the present invention, wherein FIG. 5A is a plan view thereof, and FIG. 5B is a sectional view taken along line BB in FIG.

6A and 6B show a third embodiment of the present invention, wherein FIG. 6A is a plan view thereof, and FIG. 6B is a sectional view taken along line CC in FIG.

7A and 7B show a fourth embodiment of the present invention, wherein FIG. 7A is a plan view thereof, and FIG. 7B is a sectional view taken along line DD in FIG. 7A.

8A and 8B show a fifth embodiment of the present invention, wherein FIG. 8A is a plan view thereof, and FIG. 8B is a sectional view taken along line EE in FIG. 8A.

FIG. 9 is a vertical sectional view of a sixth embodiment of the present invention.

FIG. 10 is a longitudinal sectional view of a seventh embodiment of the present invention.

FIG. 11 is a longitudinal sectional view of an eighth embodiment of the present invention.

12A and 12B are diagrams illustrating an example of a method of forming a spherical concave curved surface.

FIG. 13 is a schematic exploded perspective view showing an example of a conventional seismic isolation table.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Base plate 3 Middle plate 4 Spherical concave curved surface 5 Free bearing 5a Spherical rotating body 5b Bearing base 5c Bearing 7 Seismic isolation base mounting bracket 8 Brake collar 9 Friction member 10 Spring 13 Magnetic cylinder 14 Magnetic ring 15 Guide cylinder 16 Spherical rotating body 17 Core plate 18 Machined plate 19 Breath plate 20 Slide rail

Claims (9)

[Claims] 1. A base plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and a middle plate interposed between the base plate and the substrate. On each of the upper and lower surfaces, three or more spherical concave curved surfaces are formed, and on the upper surface of the substrate and the lower surface of the base plate, the spherical concave curved surfaces formed on the upper and lower surfaces of the middle plate are opposed to each other. A free bearing having a rotatable spherical rotating body at the tip is fixedly mounted so as to abut on the center position of the opposed spherical concave curved surface, and the rolling of each abutting spherical concave curved surface and the spherical rotating body is performed. A seismic isolation table characterized in that the base plate and the middle plate are swingable in all directions of 360 ° in a horizontal direction while maintaining a horizontal state by an action. 2. A base plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and an intermediate plate interposed between the base plate and the substrate. On the lower surface of the base plate, three or more spherical concave curved surfaces are formed, and on the upper and lower surfaces of the middle plate, the spherical concave curved surfaces formed on the upper surface of the substrate and the lower surface of the base plate are formed. Opposing free bearings each having a rotatable spherical rotating body at the tip are fixedly mounted so as to abut on the center positions of the opposed spherical concave curved surfaces, respectively. The seismic isolation table is characterized in that the base plate and the middle plate are allowed to swing in all directions of 360 ° in a horizontal direction while the horizontal state is maintained by the rolling action of the base plate and the middle plate. 3. A base plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and a middle plate interposed between the base plate and the substrate. On each of the upper and lower surfaces, three or more spherical concave curved surfaces are formed, and on the upper surface of the substrate and the lower surface of the base plate, the spherical concave curved surfaces formed on the upper and lower surfaces of the middle plate are opposed to each other. Spherical concave curved surfaces are formed respectively, and a rotatable spherical rotator is sandwiched between the spherical concave surfaces facing each other vertically, and the rolling action of each abutting spherical concave surface and the spherical rotator, A seismic isolation table characterized in that the base plate and the middle plate can be swung in all directions of 360 ° in a horizontal direction while maintaining the horizontal state. 4. A base plate on which a protective article is placed, a substrate placed on an installation surface such as a floor, and a middle plate interposed between the base plate and the substrate. On each of the upper and lower surfaces, three or more spherical concave curved surfaces are formed, and on the upper surface of the substrate, spherical concave curved surfaces are formed opposite to the spherical concave curved surfaces formed on the lower surface of the middle plate, A rotatable spherical rotator is sandwiched between the opposed spherical concave curved surfaces, and a lower surface of the base plate is opposed to each spherical concave surface formed on an upper surface of the middle plate, and is provided at a tip thereof. Free bearings having rotatable spherical rotating bodies are fixedly mounted so as to abut on the center positions of the opposed spherical concave curved surfaces, respectively, and by the rolling action of each abutting spherical concave curved surface and the spherical rotating body, While the base plate and the middle plate are kept horizontal, MenShindai, characterized in that the swingable in all directions in °. 5. The seismic isolation table according to claim 1, wherein a brake mechanism for damping horizontal swing is provided between the base plate and the middle plate and between the middle plate and the base plate. . 6. The seismic isolation table according to claim 5, wherein said brake mechanism is a contact friction type brake mechanism utilizing frictional resistance. 7. The seismic isolation table according to claim 5, wherein the brake mechanism is a magnetic repulsion type brake mechanism using magnetic repulsion between permanent magnets having the same polarity. 8. The seismic isolation table according to claim 5, wherein said brake mechanism is a gravity pull-back type brake mechanism having a curved surface in which a peripheral portion of a spherical concave curved surface rises more steeply than a central portion. 9. The curvature radius of a spherical concave curved surface located above the middle plate and a spherical concave curved surface located below the middle plate with the middle plate as a boundary, being different from each other. The base isolation table according to any one of Items 1 to 8.